So, I bought Palit GTS 250 (512MB) card about a year ago. Some review said it would be a quiet card. It even had heatpipes, so I thought maybe they really had invested some thought to cooling.

Well, not quiet enough. Maybe I am a little disappointed because with only the integrated graphics, my system is VERY silent, as in you couldn't tell whether it's on unless you are closer than 1 meter to it. (The G965 used to run dangerously hot, but I got Noctua's NC-U6 chipset heatsink and I am very pleased with it.)

So now I'm finally about to buy a third party cooler. I have no intentions to overclock. I want total silence when idle (Linux), but I also game on Windows, so it has to be able to handle high heat load, when needed.

At the moment I've ended up to two alternatives, both with links to one review and the official homepage (feel free to suggest more alternatives, although my country may have limited selection, only few really "enthusiasm"-centered retailers):

At the moment I have one 120mm fan as a combined front fan and HDD cooler, which I could basically re-allocate for the Prolimatech cooler, if needed. But the Twin Turbo would have it's own fans, which according to reviews are quiet and efficient.

I also thought I would buy Zalman FanMate2 (*), so I could at least that way disable the fan(s) altogether while using Linux (idle). I think Linux nVidia drivers set the minimum fan speed to 30% or so. (Now 46C with 35%. CPU and system temp around 40C, ambient about 23C)

(*) And after some research I found instructions for a homemade fan controller. At the moment the only question is whether it would be safe to use a potentiometer also including a switch. Or would the switch cause too radical voltage etc. spikes to the rest of the system?

I also looked at Setsugen and Spitfire, but they didn't seem that ... efficient or convincing.

At the same time I would not try to move your one intake fan. Just supplement it with another quiet fan pulling cool air from some other opening. Otherwise your efforts to use passive cooling will just not work.

Yeah, I thought it wouldn't matter. Well, the case is Antec P150 (the PSU came with it). Mini or middle-sized, I think. Takes a full-sized MB, at least... Haven't had any major clearance problems so far (no expansion cards). I did measure it, and even the Prolimatech should fit. But either way, I have somewhat abandoned that idea.

Hmm, maybe that total silence in my previous post is a bit of an exaggeration. I don't require completely passive, just extremely quiet (if/when needed).

I just bought a switchless potentiometer (quite expensive one, FM2 would have cost less), and thought about making an RPM controller of it, and using that with one 140mm silent fan (haven't yet decided which one) and attach it to Arctic Cooling Accelero S1 Rev. 2 (basically the Twin Turbo without fans, I think). It's only 20€ and I've seen some positive feedback from Newegg user reviews. VRM cooling is a little problem on higher end cards though, but so it is with those other coolers as well. Either way, GTS 250 shouldn't have problem with that.

Hopefully I'll figure out some easy way to attach the 140mm fan to it. I've heard some people use zipties (or whatever they're called, cable ties?) and I may have to resort to that also. I even thought about getting a Silverstone's 180mm fan, but THAT won't fit in the case in any meaningful way (or to any other case I've ever owned). And I don't have any experience with Silverstone's products, so it may not even be that quiet.

I also thought about watercooling with Zalman Reserator 1 V2 (225€), but the pump is assumably very bad (via Newegg user reviews), and I would have to invest even more money for a decent pump. But that would have made both CPU and GPU passively cooled. I was quite close to ordering it, but fortunately I found out about the pump before purchase.

Well, if anybody has any recommendations for a cheap (less than 120€) and good GPU water kit/combination, they're also welcome. Unfortunately, I've come to realize that if you want any quality, they're quickly quite expensive.

Sorry, I meant to reply sooner, but I kind of just "forgot". Well, I added few extra points later but here's what I wrote about two weeks ago, but didn't send:

The parts finally arrived (waited almost two weeks for a gamepad set) and I thought I'd give you the update/final closure for this topic.

I bought Noctua's NP14 140mm fan. It's not bad, but I'm a bit disappointed. I expected a lot more on the basis of my earlier Noctua products. Well, I put it on the Accelero S1 rev2 cooler (with cable ties). Then I attached it to the homemade RPM controller.

If you have something like Noctua's ULNA adapters, you don't have to make permanent alterations to the fan's wires and you can in the future use it with other fans. Highly recommended.

So, I took one of the Noctua ULNA adapters and changed the fixed resistor in the red wire to the potentiometer connection. I also added a separate switch to the connection, so I can switch the fan completely off (*) while I'm surfing, etc. I also recommend placing the potentiometer nub and the switch on one of the case's front covers.

(*) The fan is quite silent on the lower RPMs, so this isn't really necessary. But if you have a louder fan, this could be nice. Otherwise not worth the trouble.

For my system:The overall noise is definitely lower. The 140mm fan is a little too big for the Accelero, and 120mm would have sufficed. Also the GTS250 is a little too much for the Accelero to use it passively, idle temperature is at 63C, and gaming brings it over 85C. Noise output isn't that much with a low RPM fan, so I use it at 740rpm (==100 ohm).

I made a new adapter so I could connect the fan directly to GPU's own connector, but it doesn't read the RPM. And it doesn't seem to alter the speed at all. So that was a lost effort.

Regarding spikes caused by the switch:A friend of mine suggested to just NOT put it in the same line as HDD power. I have it on the SYS_FAN connector directly on MB. At least it doesn't crash or smoke for the time being. To be on the safe side, you should consider using the switch only when powered off.

PS. I'm not sure, but I may have some thermal connection problem: sometimes it idled (@740rpm) around 45C, and nowadays it's mostly 51-53C. I read somewhere that few people had problems with the washers limiting the pressure between the heatsink and heatspreader, but I thought it made quite a solid connection. I'll have to look into it some other time.

Well, this IS getting a little one-sided, it's basically just me talking. But then it occurred to me that if it helps even one person having same/similar situation, it's worth all the hassle. So here's one (last?) update:

Hot damn!

The summer here in Finland became hotter than usual (ambient 35C), and my idle GPU temps had slowly risen to 61C (at 900rpm). The computer was a huge heat source (well, the CRT in particular...), so I decided I might as well turn it off and take the previously mentioned washers off to test whether the rumors/stories were true.

And what would you know: now I'm idling at 47C (passive gets around 59C). Street Fighter IV benchmark tops at 60C. So as an advice to all Accelero S1 rev2 owners: if you're not seeing the temperatures you were hoping for or expecting, take the thick clear washers off and see whether that will help. And about the black plastic clips on the Accelero: once you put them "on", you're pretty much stuck with them. I tried to take them off, but I was already using so much force that they might break any moment, so I decided to let them be.

One other thing to note to Noctua NP-14 owners: don't use it at full speed. Somehow (at least for me) it doesn't offer noticeably lower temperatures at 1200rpm (45C idling), but makes it definitely noisier when compared to 900rpm (47C idling) or 750rpm (48C idling). Unless you have some crazy ass leafblower going full speed next to it, in which case you might as well leave the Noctua fan also at full speed.

PS. Now that I think about it, the 1200 vs 900 temperature issue might also be because of system temperature being so high for the moment.

PS2. All that was about a month ago, I just didn't get around to posting it. Now it's idling at 43C, while ambient is at the more normal level of 23C. So taking those washers off made it about 10C cooler.